Camcorders

Almost any new digital camcorder will work great, but you want to make sure it has a high speed shutter setting.  Set the shutter speed as high as possible (which means you'll need a lot of light... day light is perfect).  You're still only shooting 30 frames per second, but each shot will be sharper (less motion blur) as the shutter speed increase.  High-end cameras can go up to as much as 1/10000th of a second, but even 1/500 would be great.  Standard, default shutter speed is 1/60th.
For playback, you can use the same camera with a remote control.  Just press play, then just before the swing press pause.  Then use the frame advance button to move 1 frame at a time.  Multiple presses of the frame button will increase the speed... to slow motion.  

Good luck!